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Discussion Starter #1
Possibly unrelated: I recently changed out my turbo, compressor wheel (ViVA 11 blade) coils (stock), plugs (1 range colder iridiums) and PCV system. I removed the fuel rail when swapping the PCV, this is the only recent work on the fuel system.

I have been getting an ECM-2900 code (Fuel Pressure Faulty Signal), which VIDA says could be my fuel pressure sensor, my pump, or my pump control module. The code does not set RIGHT AWAY, but once it does, mileage goes down, it begins backfiring more often, and eventually it will set ECM-216D and ECM-21E0 codes (both associated with running rich). My theory: the -2900 code makes the car default to setting pressure as high as possible because it cannot sense it, causing the car to run rich.

My first thought was fuel pressure sensor, since they have a bad track record. I had the original from when I changed it a few years ago, and when I put in this sensor, the car set the -2900 code immediately, so I went back to the one I have been using.

I checked fuel pressure right after clearing the codes with the newer sensor, and it was about 45 PSI at idle.

I checked the pump control module for corrosion, which was a common problem due to being mounted on the side of the tank, but my car already had the recall that moved the module, so I dismissed this as being the issue.

So, what is the next step?

1. Get another new sensor and see if that helps. ($52, easy)

2. Blindly replace the pump ($182, hard)

3. Blindly replace the Fuel pump control module ($300+ for reman/new, less if I can find used, easy)

4. Some other troubleshooting that I have not thought of?

Anyone have some insight?
 

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Discussion Starter #3
In VIDA under Diagnostics/Vehicle Communication/ECM/Advanced you can select the quick test(?) of the fuel pump. It will open up a graphic display with commanded and actual values of FP. This may help.
I have VIDA, but not DICE. I connect to my car through the IPD/MTE softloader.
 

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You can use a dvom, most decent ones have it or you can get close by converting dc volts. It's a 12v pull down duty cycle circuit.
 

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Discussion Starter #9
OK. I got DiCE working. It passed the fuel pressure test perfectly. 4 times. Any more ideas?
 

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try taking it for a drive and get Vida to monitor the pressure on a graph you can look at comparing the pump pressure to the fuel pressure reading
 

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Discussion Starter #13
Fuel pump duty cycle is about 51% at idle, with pressure being ~400kPa.
 

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Discussion Starter #15
To be clear before I pull the trigger, you mean I should replace the pump? Or the PEM?

Thank you for help!
 

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Prolly a pump, but to be sure you could Load test power/ground at the pem, verify wiring between pump and pem are good. You could also check current and d.c. to the pump. I have known good scope patterns if needed
 

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Discussion Starter #17
I tried a filter first. The old filter was very rusty and ugly, it may have been original (131k), but has at least been on there for 60k miles. Duty cycle was still 50% at idle, so I expect the code to return.
 

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Discussion Starter #19
I spoke too soon. The code came back, I had to replace the pump. Duty cycle got up to 56% before replacement, 34% after.
 
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